How to buy now?

@DivinylsFan You can buy SimPoints through the Origin app - just do a search for either SimPoints or The Sims 3 - the latter will also show you any worlds that can be bought through Origin with real-life currency. Any SimPoint-only worlds should still work for purchasing through the store.

@LauraBow thanks for trying.
Any clicking on "buy sim points" or the world with RL currency on the site, takes you to an EA page advertising its other games and a pop up that says to get the EA App because Origin is closed. Clicking on buy simpoints in the Origin launcher opens an old version of Internet Explorer that wants to change to Microsoft Edge and may or may not open the Sims 3 webpage, but then does the same thing as I described before.
The only way to buy simpoints and rl currency things is through the EA App.
So I had to download the EA App onto my laptop, install the base game on it, then buy simpoints, and Barnacle Bay through that. Then go on my PC and download it from the site into my Origin launcher on there. I probably could have downloaded it into the EA App on the laptop and save it onto a USB and then put it on my PC but that would be an extra step.
The switcheroony between the laptop EA App and the PC Origin launchers is because the EA App causes Store content, including worlds, to keep on uninstalling itself in between restarts. The only way to get it reinstalled after that is by redownloading. The EA App seems to install a mac version of Sims 3 even though it is meant to be a Windows one. Sims 3 is unplayable more than once on PC with the EA App. Luckily I do have a laptop to do that on eh.

@DivinylsFan - I host the Daily Deal thread and was checking a link I had to purchase Simpoints from Origin. I don't need to purchase simpoints but did want to provide a link for others.

I have come across the same problem as you. Every link on the Sims 3 site goes to the EA website. Entering origin . com in my browser also redirects to EA new site. I can find Sims 3 on that site but no where to purchase simpoints. (There is also no obvious search function on the EA site.) I still have the Origin app on my computer which still offers simpoints for sale. Since I do not want to purchase points, I didn't allow the transaction to complete. However, I did get to a screen to enter my method of payment. If you no longer have Origin on your computer, EA_Cade provides a link to download OriginThinSetup. I am not sure if that would work but I am curious if simpoints can be purchased with Origin Thin.

Edit to Add: I found that "Sims 3 Currency" can be purchased through the new EA App which you had said that you did. I found the answer in a thread on the EA forum . @puzzlezaddict posted the solution

Open the EA App, click My Collection, then Sims 3, then DLC, and "Sims 3 Currency" should be the first listing. This is the same as SimPoints.

"CharlieBleu;c-18306500" wrote:
I've tried buying stuff through every way I have seen and I either get an error 404 or it just won't open. I've kinda just given up.

@CharlieBleu - Have you contacted Customer Service or posted on the EA Answers HQ for Sims 3